The present invention relates to printers and, more particularly, to printers suitably used for printing on a surface of paper sheets other than a printed surface.
Heretofore, as a double side printing method it has been in practice to use a printer capable of printing on single surface only. In this printing method, printing is first executed on one surface, then the paper sheets are set again in the printer for printing on the other surface, and then printing is executed on the other surface. In this way, the double surface printing is obtained.
In this printing method, when setting paper sheets after printing on one surface in the printer for printing on the other surface, an inconvenience arises due to differences of the paper sheet feed-out route and the printing direction with individual printers. Specifically, it can not be readily judged which of the upper, lower, left and right parts of the printed surface is to be directed in the paper sheet feed-out direction in a paper sheet feeder and whether the paper sheets are to be set with the printed surface up or down in the paper sheet feeder.
Therefore, such inconvenience arises as the possibility of printing again on the printed surface and also the possibility of printing the other surface in the opposite vertical direction to the desired direction.
The present invention was made in view of the background, and it has an object of solving the above problem by providing a printer, which is hardly subject to such inconvenience, in the case of printing on the blank surface of paper sheets with the other surface thereof having already been printed, of the possibility of printing again on the printed surface and also the possibility of printing the other surface in the opposite vertical direction to the desired direction.
According to an aspect of the present invention, there is provided a printer comprising a printer body capable of single-surface printing and including a paper sheet feeding unit for setting paper sheets therein for printing and a discharging unit for discharging the paper sheets after the printing and a printer controller for controlling the printer, wherein: in the case of printing on the surface of paper sheets other than the surface printed before, the printer body can print, in response to an instruction from the printer controller, a first. symbol, which indicates that the paper sheets have to be set again in the paper sheet feeder, with upper, lower, left or right part directed in the paper sheet feed-out direction, and also with the printed surface up or down.
In the present invention, by the term xe2x80x9cthe upper, lower, left or right part of one surfacexe2x80x9d is meant either of these parts of one surface of paper sheet with a document printed thereon when the document is viewed in the right or correct direction. By the term xe2x80x9cpaper feed-out directionxe2x80x9d is meant a direction, in which paper sheet set in a paper sheet feeder is fed out into the printer body.
Desirably, the paper feeder of the printer body is provided with a showing of a second symbol, which indicates, in combination with the first symbol, at least either the upper, lower, left or right part of paper sheet or the front or back surface thereof.
The paper sheet feeding unit of the printer body is provided with a showing of a second symbol indicating, in combination with the first symbol, that the paper sheets have to be set at least either with the upper, lower, left or right part of the sheets is to be directed in the paper sheet feed-out direction or with either surface up or down.
The printer has a function of permitting selection of, when executing printing on a plurality of paper sheets, the printing of the first symbol on the first paper sheet only according to an instruction from the printer controller.
The printer has a function of permitting the selection of printing no first symbol on paper sheet according to an instruction from the printer controller.
The first symbol, when printed by a solid line, indicates setting the paper sheets in the paper sheet feeder with the printed surface up and, when printed by a dashed line, indicates setting the paper sheets in the paper sheet feeder with the printed surface down.
The first symbol and the second symbol are pointed in shape, and the pointed tips are opposite in the slant direction.
Other objects and features will be clarified from the following description with reference to attached drawings.